diff --git a/src/Network/Wai/Middleware/Consul.hs b/src/Network/Wai/Middleware/Consul.hs
--- a/src/Network/Wai/Middleware/Consul.hs
+++ b/src/Network/Wai/Middleware/Consul.hs
@@ -248,5 +248,5 @@
                _workedOK <-
                  putKey cc keyValuePut Nothing
                -- TODO respond negatively if Consul 'put' didn't work
-               respond (responseBuilder status201 [] "")
+               respond (responseBuilder status201 [] mempty)
           | otherwise = app' req respond
diff --git a/wai-middleware-consul.cabal b/wai-middleware-consul.cabal
--- a/wai-middleware-consul.cabal
+++ b/wai-middleware-consul.cabal
@@ -1,5 +1,5 @@
 name:                wai-middleware-consul
-version:             0.1.0.0
+version:             0.1.0.1
 homepage:            https://github.com/fpco/wai-middleware-consul
 synopsis:            Wai Middleware for Consul
 description:         Proxies data to/from Consul. Watches for updates.